Queue<T>.ToArray Queue<T>.ToArray Queue<T>.ToArray Queue<T>.ToArray Method

定義

Queue<T> の要素を新しい配列にコピーします。Copies the Queue<T> elements to a new array.

public:
 cli::array <T> ^ ToArray();
public T[] ToArray ();
member this.ToArray : unit -> 'T[]
Public Function ToArray () As T()

戻り値

T[]

コピーした要素を格納する新しい配列、Queue<T>します。A new array containing elements copied from the Queue<T>.

次のコード例をいくつかの方法を示します、Queue<T>ジェネリック クラスなど、ToArrayメソッド。The following code example demonstrates several methods of the Queue<T> generic class, including the ToArray method.

コード例は、既定の容量を持つ文字列のキューを作成し、使用して、 Enqueue 5 つの文字列をキューにします。The code example creates a queue of strings with default capacity and uses the Enqueue method to queue five strings. キューの状態は変更されませんが、キューの要素が列挙されます。The elements of the queue are enumerated, which does not change the state of the queue. Dequeueメソッドを使用して、最初の文字列をデキューします。The Dequeue method is used to dequeue the first string. Peekメソッドを使用して、キュー内の次の項目を確認し、Dequeueがデキューするメソッドを使用します。The Peek method is used to look at the next item in the queue, and then the Dequeue method is used to dequeue it.

ToArray配列を作成し、キューの要素をコピーするメソッドを使用し、配列に渡されます、Queue<T>を受け取るコンス トラクターIEnumerable<T>キューのコピーを作成します。The ToArray method is used to create an array and copy the queue elements to it, then the array is passed to the Queue<T> constructor that takes IEnumerable<T>, creating a copy of the queue. コピーの要素が表示されます。The elements of the copy are displayed.

配列 2 回、キューのサイズを作成、およびCopyToメソッドを使用して、配列の真中で始まる配列の要素をコピーします。An array twice the size of the queue is created, and the CopyTo method is used to copy the array elements beginning at the middle of the array. Queue<T>コンス トラクターは先頭の 3 つの null 要素を格納しているキューの 2 番目のコピーを作成するにはもう一度使用されます。The Queue<T> constructor is used again to create a second copy of the queue containing three null elements at the beginning.

Contains 「4」文字列がその後が、キューの最初のコピーのことを示すメソッドを使用、Clearメソッドは、コピーをクリアし、Countプロパティは、キューが空であることを示します。The Contains method is used to show that the string "four" is in the first copy of the queue, after which the Clear method clears the copy and the Count property shows that the queue is empty.

using System;
using System.Collections.Generic;

class Example
{
    public static void Main()
    {
        Queue<string> numbers = new Queue<string>();
        numbers.Enqueue("one");
        numbers.Enqueue("two");
        numbers.Enqueue("three");
        numbers.Enqueue("four");
        numbers.Enqueue("five");

        // A queue can be enumerated without disturbing its contents.
        foreach( string number in numbers )
        {
            Console.WriteLine(number);
        }

        Console.WriteLine("\nDequeuing '{0}'", numbers.Dequeue());
        Console.WriteLine("Peek at next item to dequeue: {0}", 
            numbers.Peek());
        Console.WriteLine("Dequeuing '{0}'", numbers.Dequeue());

        // Create a copy of the queue, using the ToArray method and the
        // constructor that accepts an IEnumerable<T>.
        Queue<string> queueCopy = new Queue<string>(numbers.ToArray());

        Console.WriteLine("\nContents of the first copy:");
        foreach( string number in queueCopy )
        {
            Console.WriteLine(number);
        }
        
        // Create an array twice the size of the queue and copy the
        // elements of the queue, starting at the middle of the 
        // array. 
        string[] array2 = new string[numbers.Count * 2];
        numbers.CopyTo(array2, numbers.Count);
        
        // Create a second queue, using the constructor that accepts an
        // IEnumerable(Of T).
        Queue<string> queueCopy2 = new Queue<string>(array2);

        Console.WriteLine("\nContents of the second copy, with duplicates and nulls:");
        foreach( string number in queueCopy2 )
        {
            Console.WriteLine(number);
        }

        Console.WriteLine("\nqueueCopy.Contains(\"four\") = {0}", 
            queueCopy.Contains("four"));

        Console.WriteLine("\nqueueCopy.Clear()");
        queueCopy.Clear();
        Console.WriteLine("\nqueueCopy.Count = {0}", queueCopy.Count);
    }
}

/* This code example produces the following output:

one
two
three
four
five

Dequeuing 'one'
Peek at next item to dequeue: two
Dequeuing 'two'

Contents of the copy:
three
four
five

Contents of the second copy, with duplicates and nulls:



three
four
five

queueCopy.Contains("four") = True

queueCopy.Clear()

queueCopy.Count = 0
 */
Imports System
Imports System.Collections.Generic

Module Example

    Sub Main

        Dim numbers As New Queue(Of String)
        numbers.Enqueue("one")
        numbers.Enqueue("two")
        numbers.Enqueue("three")
        numbers.Enqueue("four")
        numbers.Enqueue("five")

        ' A queue can be enumerated without disturbing its contents.
        For Each number As String In numbers
            Console.WriteLine(number)
        Next

        Console.WriteLine(vbLf & "Dequeuing '{0}'", numbers.Dequeue())
        Console.WriteLine("Peek at next item to dequeue: {0}", _
            numbers.Peek())    
        Console.WriteLine("Dequeuing '{0}'", numbers.Dequeue())

        ' Create a copy of the queue, using the ToArray method and the
        ' constructor that accepts an IEnumerable(Of T).
        Dim queueCopy As New Queue(Of String)(numbers.ToArray())

        Console.WriteLine(vbLf & "Contents of the first copy:")
        For Each number As String In queueCopy
            Console.WriteLine(number)
        Next
        
        ' Create an array twice the size of the queue, compensating
        ' for the fact that Visual Basic allocates an extra array 
        ' element. Copy the elements of the queue, starting at the
        ' middle of the array. 
        Dim array2((numbers.Count * 2) - 1) As String
        numbers.CopyTo(array2, numbers.Count)
        
        ' Create a second queue, using the constructor that accepts an
        ' IEnumerable(Of T).
        Dim queueCopy2 As New Queue(Of String)(array2)

        Console.WriteLine(vbLf & _
            "Contents of the second copy, with duplicates and nulls:")
        For Each number As String In queueCopy2
            Console.WriteLine(number)
        Next

        Console.WriteLine(vbLf & "queueCopy.Contains(""four"") = {0}", _
            queueCopy.Contains("four"))

        Console.WriteLine(vbLf & "queueCopy.Clear()")
        queueCopy.Clear()
        Console.WriteLine(vbLf & "queueCopy.Count = {0}", _
            queueCopy.Count)
    End Sub
End Module

' This code example produces the following output:
'
'one
'two
'three
'four
'five
'
'Dequeuing 'one'
'Peek at next item to dequeue: two
'
'Dequeuing 'two'
'
'Contents of the copy:
'three
'four
'five
'
'Contents of the second copy, with duplicates and nulls:
'
'
'
'three
'four
'five
'
'queueCopy.Contains("four") = True
'
'queueCopy.Clear()
'
'queueCopy.Count = 0

注釈

Queue<T>は変更されません。The Queue<T> is not modified. 新しい配列の要素の順序は、の先頭から要素の順序と同じ、Queue<T>の終わりにします。The order of the elements in the new array is the same as the order of the elements from the beginning of the Queue<T> to its end.

このメソッドは O (n) 操作、nCountします。This method is an O(n) operation, where n is Count.

適用対象